Libreswan VPN software

Libreswan is a free software implementation of the most widely
supported and standardized VPN protocol based on ("IPsec")
and the Internet Key Exchange ("IKE"). These
standards are produced and maintained by the Internet Engineering Task Force
("IETF").

Libreswan has been under active development for over 15
years, going back to The FreeS/WAN Project founded in 1997 by John
Gilmore and Hugh Daniel. For more information, see the project's
History.
Libreswan supports IKE versions 1 and 2. It runs on Linux 2.4 to 4.x, FreeBSD and Apple OSX.
On Linux, it can use the built-in IPsec stack ("XFRM/NETKEY") or its own IPsec stack
("KLIPS"). It uses the NSS crypto library.
The list of supported RFC's can be found at Implemented standards.

Download

Libreswan is licensed under the GNU Public License ("GPLv2"). See the
License.
It ships as part of many Linux distributions, including Fedora,
RHEL/EPEL and Arch Linux and can be installed on those systems using
the native software management tools. The source code is available
as tarball and via our git repository. Older versions, patches and
pre-compiled versions are available on our download site.

Configuration examples

Common configuration examples can be found in our Wiki.
Furthermore, our test cases also
document our behaviour. You can find test case results and log files on our daily testing site at
testing.libreswan.org. And of course, the manual
page of ipsec.conf documents the configuration options as well.